Knemometry Assessment of Short-Term Lower Leg Growth in Children with Asthma Treated with Inhaled Fluticasone Furoate

A dry powder inhaler formulation of the inhaled corticosteroid fluticasone furoate is being evaluated for use in children. We assessed short-term lower leg growth in children with asthma treated with inhaled fluticasone furoate from the ELLIPTA® inhaler versus placebo. Pre-pubertal children with persistent asthma (n=60, aged 5 to <12 years) were recruited into a randomised, double-blind, placebo-controlled, two-way crossover, non-inferiority study. The study consisted of four 2-weeks periods: Run-in, two treatment periods, one wash-out period, and a 1-week follow up period. Interventions were fluticasone furoate 50 μg and placebo once daily in the evening. Lower-leg length was measured by knemometry. Fifty-eight subjects completed both treatment periods. The LS mean growth rate was 0.31 mm/week during treatment with fluticasone furoate and 0.36 mm/week during treatment with placebo. The difference in adjusted LS mean growth rates between fluticasone furoate and placebo was -0.052 mm/week with a 95% confidence interval (CI) of -0.122 to 0.018 mm/week. This was greater than the pre-specified non-inferiority margin of -0.20 mm/week. The overall incidence of adverse events was 35% on placebo and 22% on fluticasone furoate. Inhaled fluticasone furoate 50 μg once daily in the evening was non-inferior to placebo in terms of effects on short-term lower-leg growth in children with asthma. Inhaled fluticasone furoate 50 mg was well tolerated in this study population.